Socrata was acquired by Tyler Technologies in 2018 and is now the Data and Insights division of Tyler. The platform is still powered by the same software formerly known as Socrata but you will see references to Data & Insights going forward.



Returns the minimum convex geometry that encloses all of another geometry

Works with the following datatypes:

This function works with 2.1 endpoint(s). What does this mean? »

The convex_hull(...) generates a polygon that represents the minimum convex geometry that can encompass another geometry. All of the points in the input geometry will either represent vertexes of that polygon, or will be enclosed within it, much like if you were to take a rubber band and snap it around the set of points. The below image from Wikipedia may help explain better:

Convex Hull

For example, to get the convex hull that surrounds all of the crimes in Chicago in 2014:$select=count(*),convex_hull(spatial_union(location))&year=2014

This can be very useful in generating heat maps or to describe the geographic area affected by a given dataset.